Hi i'm getting a turbo motor put in at the moment into my n/a rx7, just wondering if my diff, transmission and various other drivline components would hold up and not break, if driven very very gently. These parts will eventually get replaced!
thanks.

 

you should be alright if you take it easy, and if they are getting replaced soon

 

Yea it will work fine i mean its not going to just break if you punch it or something, Remember there are na's out there that are producing more or equal the amount of hp that a tii is. Just dont launch it . And you will have no problem's.

 

yes it will work you will have to use all N/A parts like the flywheel, clutch, tranny, driveshaft, rearend and axles.

 

He's putting the motor into an na rx-7.

 

It'll work for a little bit of punching it also. I'm not sure about the tranny, but the diff will hold for some weaker burn-outs.

 

As long as you don't abuse the tranny and launch hard, it should hold up fine. I believe Aroncake was/is using the n/a drivetrain on his high comp n/a turbo motor. Maybe he will come in and let you know how the tranny held up.

 

yeh I used my NA tranny for a good 7 months (it was putting down about 260 Rwhp) at the time.

It was fine untill I killed it at the drag strip on a hard launch (3rd go of the night), then I put in another NA box (their about 200AUD) and that lasted 2 weeks then put in another NA box and that lasted about a month.... So then upgraded the Box to a turbo one and havn't had a problem.

Im also now getting 340Rwhp and the stock NA non-lsd Diff is holding fine. from my experance you will kill the box way b4 you kill your diff.

save the hassle and go to the turbo box if you can afford it.

 

it will be fine
shift it softer than you normally would
launch it softer

 

For those that have blown the NA tranny, what was the cause? what failed?
Did you disassemble the tranny and inspect broken parts? pictures? how old was the fluid? miles on tranny? brand of fluid? fluid level?

Maybe all those hi-mileage tired old lubed NA trannies CAN handle power---- after a rebuild using some heat treating, lube coatings, cryo'ing, bluprinting, new bearings, metal-lax, REM finishing, light flywheel, aluminum/CF driveshafts, new seals that don't leak, synthetic gear oil, shifter bushings,.................

I also don't see an unlimited supply of cheap good T2 trannies, driveshafts, rearends, axles....

 

Kevin took apart a NA transmission after it blew up on his turbo'd car.

The teeth on the input gear for the countershaft had all sheared off. The metal used in assorted parts of the NA transmissions is weaker than the metal used in the same pieces of the TII transmissions.

-=Russ=-

 

I killed two due to lack of oil.

1st one had ~230,000 kilometers on it. The rear seal must have let go as I entered the highway, because shortly thereafter it blew while I was climbing a hill (at 10 PSI of boost). There was a whinning noise that started and within a 10 second period turned into a loud screeching, then a "BANG!" and then the car started to slow down wile the engine hit 8000 RPM. When I got it home, I found the input shaft had snapped.

2nd one also failed due to lack of oil. The front seal was leaking slowly and it ran too dry for too long. It never actually failed, but picked up a loud bearing whine. I had that transmission rebuilt and the shop replaced the input shaft, cluster shaft and bearings.

 

I am still using the rearend. It's holding up BUT the LSD is gone now.
130k on the rearend and 30k of that being the higher 13bt motor make quick work of it. It's now open diff one wheel tire fire.

 

Putting the power down is what will cause the problem on a NA drivetrain. You will be fine on the street because wheel spin takes away some of the stress.

 

Add shotpeening and mikroniting to my above list.

So, lack of lube or a bad shift seems to be causing the majority of failures. I top my gear oil off at every oil change cause of a tiny seal leak, which will be fixed when the clutch finally blows. Has anyone checked/changed your gear oil in the past 20 years?

Metal can be treated to be stronger. Power isn't the only things that destroys gears/shafts. Lack of lubrication, excessive heat, and tranny slack, can do a lot to chip/ding/wear/weaken/break gears.

I don't see the transmission as a weak link. I believe that the owner is. Sure, it isn't big enough for a ton of power, but it should be good enough if rebuilt and taken care of.

Any 15-20 year old tranny should be 'gone over' prior to use with higher HP.

 

I just want to be clear that I BEAT THE HELL out of my NA transmission on the drag strip in both NA and turbo form. I even sheared off the front u-joint on a hard launch back when the car was NA. Recently, I had my upgraded "unbreakable" driveshaft serviced. This is a custom shaft I had a driveline shop in London make using full size Dodge truck u-joints. The driveline guy was amazed that I had managed to destroy BOTH u-joints and the rear flange and not blow up the transmission. The NA transmission is not as weak as most people seem to think.